After days of historic flooding, University of Colorado officials announced the school will re-open Monday -- an unpopular decision with students who immediately began circulating a petition to keep the school closed and took to social media to criticize the move.

Meanwhile, the Boulder Valley School District announced it will keep all of its schools closed Monday and Tuesday.

Naropa University also canceled Monday classes, and a letter from the school's president, Chuck Lief, said the decision was made partly because about 50 classes were at risk of cancellation anyway given that several faculty members couldn't travel to Boulder. However, Naropa will open all three of its campuses in order to allow the community places to "gather, receive and offer support to one another."

CU called off classes and shut the campus down beginning Thursday and canceled Saturday's football game against Fresno State. But Chancellor Phil DiStefano announced Sunday afternoon that the school will re-open Monday with the cautionary note that students and employees don't take any "dangerous risks" to get to campus.

The provost's office has asked faculty members to be flexible with students immediately impacted by the flood.

"We're not expecting anyone to take any heroic measures to get to campus," CU spokesman Bronson Hilliard said.

Students, though, slammed CU for a decision that some described as insensitive -- snarking that they'd need to hitch a ride with the National Guard because of the road closures near their homes or get tetanus shots because of a raw sewage spill reported Sunday afternoon on the East Campus.

An anonymous student circulated a petition saying it's unsafe for students, faculty and staff to commute to CU when it's in the middle of a national disaster area.

Monica Koenig, a CU graduate student who teaches a creative writing class, sent an email to her students saying that "nothing is worth compromising their safety." Her Monday class will be a relaxed day for students who, like her, are going stir crazy.

Koenig said the last couple of days have been stressful as her parents are stranded in Allenspark.

She said CU's decision to re-open is "irresponsible."

Hilliard acknowledged the decision has not been a popular one, but said CU officials will work with anyone directly impacted by the flood.

"We're going to show the maximum flexibility to our faculty, staff and students as they cope with the personal losses and challenges of the disaster," he said.

CU officials said students who have been displaced or otherwise affected should notify their professors and instructors. Supervisors of campus employees are also being asked to be understanding of the serious impact the flooding has had on some employees.

Nate King, a CU senior studying advertising, said he disagreed with the university's decision to re-open.

"I think the announcement was intended to be a rallying call that we're going to get through this and that we're trying to return to normal," King said. "But the fact is, we're still a disaster area."

King said his own home was unaffected and he was able to go to his part-time food service job in the dorms when the campus was closed last week.

"I'm lucky to not have been affected, but so many students have lost their houses, dogs are missing and more than 300 people are unaccounted for," Frank said. "There's so much devastation."

Although several CU buildings were damaged by the flooding, all classrooms and business service offices will be operational. It is possible some courses will be canceled or rescheduled because of instructors' availability.

CU officials said it appears the worst of the weather has passed, but afternoon thunderstorms are still in the forecast for the next few days and they ask people on the campus to stay on alert for flash flood conditions and avoid creeks and flooded areas.

"Deans of CU's colleges and schools reported to the provost that a majority of faculty members are available to hold classes Monday.

"We have a critical mass of faculty to hold classes," Hilliard said.

Officials from the Boulder Valley School District will communicate with families Tuesday about what the plans are for the rest of the week. Families were told that BVSD teachers will adjust assignment due dates and expectations for students given the number of days away from school.

BVSD students have been out of school since Thursday.

"Some of the short-term concerns with school district facilities are being addressed as quickly as possible by district personnel as well as outside restoration contractors," Superintendent Bruce Messinger said in a statement. "There are some long-term challenges facing students, families and employees which will take longer to resolve. The inability for students and staff to travel between our communities presents some unique challenges. There are also many families and staff who have been evacuated to locations outside of BVSD. I will be meeting with district and school administration on Monday to address both the short and long term issues."

Students in the St. Vrain Valley School District will be out until at least Thursday.